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πŸ”— HN as a credible source in Wikipedia?

πŸ”— California πŸ”— Companies πŸ”— California/San Francisco Bay Area πŸ”— Video games

Zynga Inc. is an American social game developer running social video game services and founded in April 2007 with headquarters in San Francisco, California, United States. The company primarily focuses on mobile and social networking platforms. Zynga states its mission as "connecting the world through games."

Zynga launched its best-known game, FarmVille, on Facebook in June 2009, reaching 10 million daily active users (DAU) within six weeks. As of August 2017, Zynga had 30 million monthly active users (MAU). In 2017 its most successful games were Zynga Poker and Words with Friends 2, with about 57 million games being played at any given moment; and CSR Racing 2, the most popular racing game on mobile devices.

Zynga began trading on NASDAQ December 16, 2011, under the ticker ZNGA.

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πŸ”— Work expands so as to fill the time available for its completion

πŸ”— Economics πŸ”— Systems πŸ”— Business πŸ”— Sociology πŸ”— Organizations πŸ”— Engineering πŸ”— Systems/Project management

Parkinson's law is the adage that "work expands so as to fill the time available for its completion". It is sometimes applied to the growth of bureaucracy in an organization.

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πŸ”— Ludic Fallacy

πŸ”— Philosophy πŸ”— Philosophy/Logic

The ludic fallacy, identified by Nassim Nicholas Taleb in his book The Black Swan (2007), is "the misuse of games to model real-life situations". Taleb explains the fallacy as "basing studies of chance on the narrow world of games and dice". The adjective ludic originates from the Latin noun ludus, meaning "play, game, sport, pastime".

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πŸ”— List of selected stars for navigation

πŸ”— Lists πŸ”— Transport πŸ”— Transport/Maritime

Fifty-eight selected navigational stars are given a special status in the field of celestial navigation. Of the approximately 6,000Β stars visible to the naked eye under optimal conditions, the selected stars are among the brightest and span 38 constellations of the celestial sphere from the declination of βˆ’70Β° to +89Β°. Many of the selected stars were named in antiquity by the Babylonians, Greeks, Romans, and Arabs.

The star Polaris, often called the "North Star", is treated specially due to its proximity to the north celestial pole. When navigating in the Northern Hemisphere, special techniques can be used with Polaris to determine latitude or gyrocompass error. The other 57Β selected stars have daily positions given in nautical almanacs, aiding the navigator in efficiently performing observations on them. A second group of 115Β "tabulated stars" can also be used for celestial navigation, but are often less familiar to the navigator and require extra calculations.

For purposes of identification, the positions of navigational stars β€” expressed as declination and sidereal hour angle β€” are often rounded to the nearest degree. In addition to tables, star charts provide an aid to the navigator in identifying the navigational stars, showing constellations, relative positions, and brightness.

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πŸ”— Halbach Magnetic Array

πŸ”— Physics

A Halbach array (German: [ˈhalbax]) is a special arrangement of permanent magnets that augments the magnetic field on one side of the array while cancelling the field to near zero on the other side. This is achieved by having a spatially rotating pattern of magnetisation.

The rotating pattern of permanent magnets (on the front face; on the left, up, right, down) can be continued indefinitely and have the same effect. The effect of this arrangement is roughly similar to many horseshoe magnets placed adjacent to each other, with similar poles touching.

This magnetic orientation process replicates that applied by a magnetic recording tape head to the magnetic tape coating during the recording process. The principle was further described by James (Jim) M. Winey of Magnepan in 1970, for the ideal case of continuously rotating magnetization, induced by a one-sided stripe-shaped coil.

The effect was also discovered by John C. Mallinson in 1973, and these "one-sided flux" structures were initially described by him as a "curiosity", although at the time he recognized from this discovery the potential for significant improvements in magnetic tape technology.

Physicist Klaus Halbach, while at the Lawrence Berkeley National Laboratory during the 1980s, independently invented the Halbach array to focus particle accelerator beams.

πŸ”— Star Lifting

πŸ”— Architecture

Star lifting is any of several hypothetical processes by which a sufficiently advanced civilization (specifically, one of Kardashev-II or higher) could remove a substantial portion of a star's matter which can then be re-purposed, while possibly optimizing the star's energy output and lifespan at the same time. The term appears to have been coined by David Criswell.

Stars already lose a small flow of mass via solar wind, coronal mass ejections, and other natural processes. Over the course of a star's life on the main sequence this loss is usually negligible compared to the star's total mass; only at the end of a star's life when it becomes a red giant or a supernova is a large proportion of material ejected. The star lifting techniques that have been proposed would operate by increasing this natural plasma flow and manipulating it with magnetic fields.

Stars have deep gravity wells, so the energy required for such operations is large. For example, lifting solar material from the surface of the Sun to infinity requires 2.1 Γ— 1011 J/kg. This energy could be supplied by the star itself, collected by a Dyson sphere; using 10% of the Sun's total power output would allow 5.9 Γ— 1021 kilograms of matter to be lifted per year (0.0000003% of the Sun's total mass), or 8% of the mass of Earth's moon.

πŸ”— Teuvo Kohonen Has Died

πŸ”— Biography

Teuvo Kalevi Kohonen (11 July 1934 – 15 December 2021) was a prominent Finnish academic (Dr. Eng.) and researcher. He was professor emeritus of the Academy of Finland.

Prof. Kohonen made many contributions to the field of artificial neural networks, including the Learning Vector Quantization algorithm, fundamental theories of distributed associative memory and optimal associative mappings, the learning subspace method and novel algorithms for symbol processing like redundant hash addressing. He has published several books and over 300 peer-reviewed papers.

Kohonen’s most famous contribution is the Self-Organizing Map (also known as the Kohonen map or Kohonen artificial neural networks, although Kohonen himself prefers SOM). Due to the popularity of the SOM algorithm in many research and in practical applications, Kohonen is often considered to be the most cited Finnish scientist. The current version of the SOM bibliography contains close to 8000 entries.

During most of his career, Prof. Kohonen conducted research at Helsinki University of Technology (TKK). The Neural Networks Research Centre of TKK, a center of excellence appointed by Academy of Finland was founded to conduct research related to Teuvo Kohonen's innovations. After Kohonen's retirement, the center was led by Prof. Erkki Oja and later renamed to Adaptive Informatics Research Centre with widened foci of research.

Teuvo Kohonen was elected the First Vice President of the International Association for Pattern Recognition from 1982 to 1984, and acted as the first president of the European Neural Network Society from 1991 to 1992.

For his scientific achievements, Prof. Kohonen has received a number of prizes including the following:

  • IEEE Neural Networks Council Pioneer Award, 1991
  • Technical Achievement Award of the IEEE Signal Processing Society, 1995
  • IEEE Frank Rosenblatt Award, 2008

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πŸ”— The Amiga Smart File System

πŸ”— Computing πŸ”— Computing/Amiga

The Smart File System (SFS) is a journaling filesystem used on Amiga computers and AmigaOS-derived operating systems (though some support also exists for IBM PC compatibles). It is designed for performance, scalability and integrity, offering improvements over standard Amiga filesystems as well as some special or unique features.

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πŸ”— Bohm Dialogue

Bohm Dialogue (also known as Bohmian Dialogue or "Dialogue in the Spirit of David Bohm") is a freely flowing group conversation in which participants attempt to reach a common understanding, experiencing everyone's point of view fully, equally and nonjudgementally. This can lead to new and deeper understanding. The purpose is to solve the communication crises that face society, and indeed the whole of human nature and consciousness. It utilizes a theoretical understanding of the way thoughts relate to universal reality. It is named after physicist David Bohm who originally proposed this form of dialogue.

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